Hallmark Card Studio 2018 and earlier are not compatible with macOS Catalina (10.15). We are recommending that you do not upgrade to macOS Catalina if you want to continue using the old versions.
We do have an update if you have Hallmark Card Studio for Mac 2019. This free update brings full macOS Catalina support to Hallmark Card Studio 2019.
The current version (release for 2020) is also compatible with Catalina. For details, please visit product page
Unfortunately we will not have updates for any previous versions of Hallmark Card Studio for Mac.